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arXiv · 1511.01283

Design and performance of an ionisation chamber for the measurement of low alpha-activities

Andreas Hartmann·Jochen Hutsch·Felix Krüger·Manfred Sobiella·Heinrich Wilsenach·Kai Zuber
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Abstract

A new ionisation chamber for alpha-spectroscopy has been built from radio-pure materials for the purpose of investigating long lived alpha-decays. The measurement makes use of pulse shape analysis to discriminate between signal and background events. The design and performance of the chamber is described in this paper. A background rate of ($10.9 \pm 0.6$) counts per day in the energy region of 1 MeV to 9 MeV was achieved with a run period of 30.8 days. The background is dominantly produced by radon daughters.

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Andreas Hartmann, Jochen Hutsch, Felix Krüger, Manfred Sobiella, Heinrich Wilsenach, Kai Zuber. 2015-11-04. Design and performance of an ionisation chamber for the measurement of low alpha-activities. https://doi.org/10.1016/j.nima.2016.01.033

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